Data-Centers-NC-v4 EQc9: Acoustic performance

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Credit language

Requirements

For all occupied spaces, meet the following requirements, as applicable, for HVAC background noise, sound isolation, reverberation time, and sound reinforcement and masking.

HVAC Background Noise

Achieve maximum background noise levels from heating, ventilating, and air conditioning (HVAC) systems per 2011 ASHRAE Handbook, HVAC Applications, Chapter 48, Table 1; AHRI Standard 885-2008, Table 15; or a local equivalent. Calculate or measure sound levels. For measurements, use a sound level meter that conforms to ANSI S1.4 for type 1 (precision) or type 2 (general purpose) sound measurement instrumentation, or a local equivalent. Comply with design criteria for HVAC noise levels resulting from the sound transmission paths listed in ASHRAE 2011 Applications Handbook, Table 6; or a local equivalent.

Sound Isolation

Meet the composite sound transmission class (STCC) ratings listed in Table 1, or local building code, whichever is more stringent.

Table 1. Minimum composite sound transmission class ratings for adjacent spaces

Adjacency combinations		STC_C
Residence (within a multifamily residence), hotel or motel room	Residence, hotel or motel room	55
Residence, hotel or motel room	Common hallway, stairway	50
Residence, hotel or motel room	Retail	60
Retail	Retail	50
Standard office	Standard office	45
Executive office	Executive office	50
Conference room	Conference room	50
Office, conference room	Hallway, stairway	50
Mechanical equipment room	Occupied area	60

Reverberation Time

Meet the reverberation time requirements in Table 3 (adapted from Table 9.1 in the Performance Measurement Protocols for Commercial Buildings¹).

Table 2. Reverberation time requirements

Room type	Application	T60 (sec), at 500 Hz, 1000 Hz, and 2000 Hz
Apartment and condominium	—
Hotel/motel	Individual room or suite
Hotel/motel	Meeting or banquet room
Office building	Executive or private office
	Conference room
	Teleconference room
	Open-plan office without sound masking
	Open-plan office with sound masking
Courtroom	Unamplified speech
Courtroom	Amplified speech
Performing arts space	Drama theaters, concert and recital halls	Varies by application
Laboratories	Testing or research with minimal speech communication
Laboratories	Extensive phone use and speech communication
Church, mosque, synagogue	General assembly with critical music program	Varies by application
Library
Indoor stadium, gymnasium	Gymnasium and natatorium
Indoor stadium, gymnasium	Large-capacity space with speech amplification
Classroom	—

Sound Reinforcement and Masking Systems

Sound Reinforcement For all large conference rooms and auditoriums seating more than 50 persons, evaluate whether sound reinforcement and AV playback capabilities are needed. If needed, the sound reinforcement systems must meet the following criteria:

Achieve a speech transmission index (STI) of at least 0.60 or common intelligibility scale (CIS) rating of at least 0.77 at representative points within the area of coverage to provide acceptable intelligibility.
Have a minimum sound level of 70 dBA and must
Maintain sound-level coverage within +/–3 dB at the 2000 Hz octave band throughout the space.

Masking Systems For projects that use masking systems, the design levels must not exceed 48 dBA. Ensure that loudspeaker coverage provides uniformity of +/–2 dBA and that speech spectra are effectively masked.

¹ Adapted from ASHRAE (2007d), ASA (2008), ANSI (2002), and CEN (2007)

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Cost estimates for this credit

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Frequently asked questions

Is it possible to pursue this as an Innovation credit in a Core & Shell project? The answer to this question is available to LEEDuser premium members. Start a free trial » (If you're already a premium member, log in here.)
Our project has small meeting rooms in an open-office plan. This situation appears to require an STC of 50. However, this level seems to be (unrealistically) high, especially considering the doors in the wall partition. STC 50 with a (closed) wall can be achieved, but even high STC doors won't achieve an STC of more than 45. Would this mean that the credit is not achievable? The answer to this question is available to LEEDuser premium members. Start a free trial » (If you're already a premium member, log in here.)
Sound transmission requirements for adjacency combinations are listed in Reference Guide Table 1, but not all combinations are included. For example, an STC rating requirement is not provided for conference room and standard/executive office adjacency. Is sound transmission compliance achieved by addressing only project applicable adjacency combinations listed in Table 1? The answer to this question is available to LEEDuser premium members. Start a free trial » (If you're already a premium member, log in here.)
Are we required to have an acoustical consultant in order to attempt this credit? The answer to this question is available to LEEDuser premium members. Start a free trial » (If you're already a premium member, log in here.)

See all forum discussions about this credit »

Addenda

4/6/2018 – Updated: 11/6/2020

Reference Guide Correction

Description of change:

Add an International Tips section that reads:

"The International Electrotechnical Commission (2013) IEC 61672-1:2013 Electroacoustics – Sound Level Meters – Part 1: Specifications are considered to be an equivalent to ANSI S1.4. Project teams outside the U.S. may use measuring equipment which is in line with IEC 61672-1:2013."

Campus Applicable

Internationally Applicable:

Yes

4/6/2018 – Updated: 5/1/2018

Rating System Correction

Description of change:

In Table 2, revise the T60 value for Office Building Open Plan Office with Sound Masking to read as "

Campus Applicable

Internationally Applicable:

7/11/2017 – Updated: 7/18/2017

Form Update

Description of change:

Updated Sound Transmission (Isolation) tab to allow for "other" space type

Campus Applicable

Yes

Internationally Applicable:

Yes

4/1/2015 – Updated: 4/1/2015

Reference Guide Correction

Description of change:

Replace TABLE 1 header with: TABLE 1. Minimum composite sound transmission class ratings for adjacent spaces

Campus Applicable

Internationally Applicable:

4/1/2015 – Updated: 4/1/2015

Rating System Correction

Description of change:

Replace TABLE 1 header with: TABLE 1. Minimum composite sound transmission class ratings for adjacent spaces

Campus Applicable

Internationally Applicable:

10/1/2014 – Updated: 2/14/2015

Form Update

Description of change:

Revised Instructions and Summary tabs to include ID+C rating systems

Campus Applicable

Internationally Applicable:

10/1/2014 – Updated: 2/14/2015

Reference Guide Correction

Description of change:

Change 'Equation 1' to 'Equation 2' so the first sentence reads "Equation 2 must be calculated separately..."
Renumber Equation 1 to Equation 2.
Renumber Equation 2 to Equation 3.
Renumber Equation 3 to Equation 4.

Campus Applicable

Internationally Applicable:

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Ken Shook

LEED AP BD+C

Longman Lindsey
Partner

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Credit language

Requirements

For all occupied spaces, meet the following requirements, as applicable, for HVAC background noise, sound isolation, reverberation time, and sound reinforcement and masking.

HVAC Background Noise

Sound Isolation

Meet the composite sound transmission class (STCC) ratings listed in Table 1, or local building code, whichever is more stringent.

Table 1. Minimum composite sound transmission class ratings for adjacent spaces

Adjacency combinations		STC_C
Residence (within a multifamily residence), hotel or motel room	Residence, hotel or motel room	55
Residence, hotel or motel room	Common hallway, stairway	50
Residence, hotel or motel room	Retail	60
Retail	Retail	50
Standard office	Standard office	45
Executive office	Executive office	50
Conference room	Conference room	50
Office, conference room	Hallway, stairway	50
Mechanical equipment room	Occupied area	60

Reverberation Time

Meet the reverberation time requirements in Table 3 (adapted from Table 9.1 in the Performance Measurement Protocols for Commercial Buildings¹).

Table 2. Reverberation time requirements

Room type	Application	T60 (sec), at 500 Hz, 1000 Hz, and 2000 Hz
Apartment and condominium	—
Hotel/motel	Individual room or suite
Hotel/motel	Meeting or banquet room
Office building	Executive or private office
	Conference room
	Teleconference room
	Open-plan office without sound masking
	Open-plan office with sound masking
Courtroom	Unamplified speech
Courtroom	Amplified speech
Performing arts space	Drama theaters, concert and recital halls	Varies by application
Laboratories	Testing or research with minimal speech communication
Laboratories	Extensive phone use and speech communication
Church, mosque, synagogue	General assembly with critical music program	Varies by application
Library
Indoor stadium, gymnasium	Gymnasium and natatorium
Indoor stadium, gymnasium	Large-capacity space with speech amplification
Classroom	—

Sound Reinforcement and Masking Systems

Achieve a speech transmission index (STI) of at least 0.60 or common intelligibility scale (CIS) rating of at least 0.77 at representative points within the area of coverage to provide acceptable intelligibility.
Have a minimum sound level of 70 dBA and must
Maintain sound-level coverage within +/–3 dB at the 2000 Hz octave band throughout the space.

¹ Adapted from ASHRAE (2007d), ASA (2008), ANSI (2002), and CEN (2007)

What does it cost?

Cost estimates for this credit

This information is also available in a full PDF download in The Cost of LEED v4 report.

Learn more about The Cost of LEED v4 »

Documentation toolkit

In the end, LEED is all about documentation. LEEDuser’s Documentation Toolkit, for premium members only, saves you time and helps you avoid mistakes with:

Calculators to help assess credit compliance.
Tracking spreadsheets for materials purchases.
Spreadsheets and forms to give to subs and other team members.
Guidance documents on arcane LEED issues.
Sample templates to help guide your narratives and LEED Online submissions.
Examples of actual submissions from certified LEED projects.

FAQ

Is it possible to pursue this as an Innovation credit in a Core & Shell project? The answer to this question is available to LEEDuser premium members. Start a free trial » (If you're already a premium member, log in here.)
Our project has small meeting rooms in an open-office plan. This situation appears to require an STC of 50. However, this level seems to be (unrealistically) high, especially considering the doors in the wall partition. STC 50 with a (closed) wall can be achieved, but even high STC doors won't achieve an STC of more than 45. Would this mean that the credit is not achievable? The answer to this question is available to LEEDuser premium members. Start a free trial » (If you're already a premium member, log in here.)
Sound transmission requirements for adjacency combinations are listed in Reference Guide Table 1, but not all combinations are included. For example, an STC rating requirement is not provided for conference room and standard/executive office adjacency. Is sound transmission compliance achieved by addressing only project applicable adjacency combinations listed in Table 1? The answer to this question is available to LEEDuser premium members. Start a free trial » (If you're already a premium member, log in here.)
Are we required to have an acoustical consultant in order to attempt this credit? The answer to this question is available to LEEDuser premium members. Start a free trial » (If you're already a premium member, log in here.)

Addenda

4/6/2018 – Updated: 11/6/2020

Reference Guide Correction

Description of change:

Campus Applicable

Internationally Applicable:

Yes

4/6/2018 – Updated: 5/1/2018

Rating System Correction

Description of change:

In Table 2, revise the T60 value for Office Building Open Plan Office with Sound Masking to read as "

Campus Applicable

Internationally Applicable:

7/11/2017 – Updated: 7/18/2017

Form Update

Description of change:

Updated Sound Transmission (Isolation) tab to allow for "other" space type

Campus Applicable

Yes

Internationally Applicable:

Yes

4/1/2015 – Updated: 4/1/2015

Reference Guide Correction

Description of change:

Replace TABLE 1 header with: TABLE 1. Minimum composite sound transmission class ratings for adjacent spaces

Campus Applicable

Internationally Applicable:

4/1/2015 – Updated: 4/1/2015

Rating System Correction

Description of change:

Replace TABLE 1 header with: TABLE 1. Minimum composite sound transmission class ratings for adjacent spaces

Campus Applicable

Internationally Applicable:

10/1/2014 – Updated: 2/14/2015

Form Update

Description of change:

Revised Instructions and Summary tabs to include ID+C rating systems

Campus Applicable

Internationally Applicable:

10/1/2014 – Updated: 2/14/2015

Reference Guide Correction

Description of change:

Campus Applicable

Internationally Applicable:

LEEDuser expert

Ken Shook

LEED AP BD+C

Longman Lindsey
Partner

See all LEEDuser forum discussions about this credit » Unsubscribe from discussions about Data-Centers-NC-v4 EQc9 View the LEED v4.1 version of this credit

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Data-Centers-NC-v4 EQc9: Acoustic performance 1 point

LEEDuser expert

Ken Shook

Frank advice from LEED experts

Requirements

HVAC Background Noise

Sound Isolation

Table 1. Minimum composite sound transmission class ratings for adjacent spaces

Reverberation Time

Table 2. Reverberation time requirements

Sound Reinforcement and Masking Systems

Cost estimates for this credit

Is it possible to pursue this as an Innovation credit in a Core & Shell project?

Are we required to have an acoustical consultant in order to attempt this credit?

The motherlode of cheat sheets

LEEDuser expert

Ken Shook

LEEDuser’s viewpoint

Get the inside scoop

Credit language

Requirements

HVAC Background Noise

Sound Isolation

Table 1. Minimum composite sound transmission class ratings for adjacent spaces

Reverberation Time

Table 2. Reverberation time requirements

Sound Reinforcement and Masking Systems

What does it cost?

Cost estimates for this credit

Documentation toolkit

FAQ

Is it possible to pursue this as an Innovation credit in a Core & Shell project?

Are we required to have an acoustical consultant in order to attempt this credit?

Addenda

LEEDuser expert

Ken Shook